结合热流密度和边界条件,根据热传导理论建立液体黏性传动装置对偶钢片瞬态热应力耦合理论模型,并采用有限元法求解。根据带式输送机实际工况,对摩擦副边界摩擦阶段的瞬态热应力耦合场进行理论和试验研究。研究结果表明:对偶钢片表面温度随对偶钢片半径r增大而升高,但是最高温度出现在r=170 mm处,并不在外径r=180 mm处,原因是外径处对偶钢片与工作油存在对流换热;径向各点的表面温度随边界摩擦时间呈指数关系增长;当边界摩擦时间15 s时,最高温度可达465.9℃,表面发生烧伤甚至胶合现象;同时,径向温度分布不均导致内应力的产生,最大热应力达832 MPa,大于材料屈服应力,对偶钢片产生塑性变形。因此,在研究液体黏性传动特性时必须考虑对偶钢片变形,以便为液黏传动装置的设计提供更可靠的理论依据。
Combining heat flux and boundary conditions of steel disk of hydro-viscous drive(HVD) device,a theory model of transient thermal stress coupling was established based on heat conduction theory.The theory model was solved using finite element method.According to the belt conveyor's actual conditions,the transient thermal stress coupling field of the steel disk was studied during the stage of boundary friction.The results show that the surface temperature of the steel disk increases with the increase of radius,while the highest temperature appears at r=170 mm,not at outer radius r=180 mm,for there is convection heat transfer between steel disk and working oil at outer radius.The surface temperatures of radial points increase with the increase of boundary friction time exponentially.Simultaneously,uneven radial temperature causes thermal stress.When the boundary friction time is 15 s,the highest temperature reaches 465.9 ℃,and there is burn even scuffing on the steel disk surface.And the thermal stress reaches 832 MPa,which is larger than the material's yield stress,which causes steel disk's plastic deformation.Therefore,in order to provide a reliable theoretical basis for the HVD device's design,steel disk's deformation must be considered while studying the characteristics of the HVD.